In this research project we plan to use a combined genetic-biochemical approach to define the organization of the adenovirus genome in terms of the location and function of the virus genes which control virus development during infection. We also hope to define the requirements for adeno genes in oncogenic transformation of rodent cells, and establish the nature and mode of action of the gene products involved in this process. We have isolated temperature-sensitive (ts) and host-range (hr) mutants of type 5 human adenovirus and of Ad2 plus ND1, and we are characterizing these genetically and physiologically. Many of the ts mutations and a few of the hr mutations have been genetically mapped and some of the ts mutations have also been mapped physically on the adeno genome by restriction analysis of intertypic recombinant DNA molecules. We aim to continue these mapping studies both genetically and physically and plan to use a marker rescue technique based on transfection with adeno DNA. Physiologically, the mutants are being characterized for DNA and protein synthesis, tumor antigen production, host-range, DNA infectivity, etc., in lytic and non-lytic interactions with cells. Some of the mutants are defective for transformation of rat cells, and potentially they bear mutations in the gene(s) required for initiation and maintenance of transformation.